TORONTO -- A man charged with first-degree murder in the death of a York University student from China had both anti-psychotic and anti-depressant medication on him when he was arrested, a jury heard Thursday.

Brian Dickson was arrested about a week after Qian Liu, 23, was found dead in her off-campus apartment, mostly naked and face down on the floor.

As a tenant in the same building and someone who matched the description of a man Liu's ex-boyfriend saw on her webcam shortly before she died, Dickson was interviewed by police on April 19, 2011.

Det.-Sgt. Frank Skubic testified Thursday that Dickson was arrested the next day, after results from DNA tests gave Skubic "reasonable grounds" to believe Dickson was responsible for Liu's death.

There were a number of medications in Dickson's room, and when Dickson was arrested he had anti-psychotic medication, a drug typically used for depression or anxiety and one that reduces the production of stomach acid, Skubic said under cross-examination from Dickson's lawyer, Robert Nuttall.

Dickson has pleaded not guilty to first-degree murder, but his lawyer has told the jury he'll be urging a finding of manslaughter.

The jury on Thursday watched Dickson's 3 1/2-hour interview with Skubic, in which he admitted he was briefly in Liu's room the night before her body was found.

Liu had been chatting with her ex-boyfriend in China via webcam when some time after 1 a.m. he saw Liu answer a knock on the door to a man who tried to hug her then forced his way inside and shoved her off camera, the Crown has said.

He heard two muffled bangs and the last image he saw was the man turning off the computer while naked from the waist down, the Crown alleges.

He then logged into Liu's account and sent frantic messages to her contacts, the trial has heard.

Yang Qiao, one of Liu's fellow students in a preparatory program, said she saw the message around 2 a.m.

"She was asking for help," Qiao testified Thursday. "It said Qian Liu is in danger. Can someone else help her? Call the police."

Dickson only met Liu a month prior, when he was doing laundry, which was located outside her room in the basement, he told Skubic in the interview.

"She was very friendly," Dickson said. "She was a very sweet person...That was my first impression, that she's nice. You could tell."

On the night in question they chatted about cooking at around 10 p.m. as Dickson put clothes in the washing machine and he was briefly inside her room, he said.

He then left the building to go to a restaurant on campus, he said, and told Skubic several times that people could verify he was there. Dickson got home around 12:30 a.m. and went downstairs to put his clothing in the dryer, but he didn't see Liu, he said.

He had taken the drug Seroquel as a sleep aid around 11:40 p.m. so he could fall asleep soon after he got home, Dickson said. Skubic asked how much alcohol he had consumed that evening and Dickson said he had three beers at home then a pitcher of beer at the restaurant.

A server at the restaurant testified Thursday that Dickson was there until closer to 1 a.m.

She served him two pints of beer, but as he was a regular customer she would have allowed him to pour his own beer from time to time, she said. His bill came to $10 and he said he would pay her back the next time, she testified.

Dickson estimated he fell asleep five minutes after going to bed, but he complained to Skubic that despite having taken the sleeping pill he was awoken several times by other residents of the house using the kitchen, stairs and front door. He only left his room once, around 5 a.m., to use the washroom and turn off the kitchen light, Dickson said.

Dickson speaks quietly, almost inaudibly, through much of the interview, and professes a desire to help with the investigation. He considers calling a lawyer, after Skubic reads him his rights for a second time following Dickson's admission he was outside Liu's room around 12:30 a.m., but he ultimately decides against it.